1. Field of the Invention
The present invention generally relates to a control circuit, and more particularly to an LED control circuit.
2. The Related Art
At present, LEDs are widely used in many electronic products for showing a working state or having a lighting function. When the LED works for a long time, the temperature of the LED will be risen such that has an influence on the lightness of the LED. So an LED control circuit capable of regulating the temperature of the LED comes with the tide of fashion.
Referring to FIG. 2, a conventional LED control circuit 1′ includes a reference voltage generator 100′ for generating a reference voltage Vref1, a non-inversion amplification unit 200′, a driving unit 300′, an LED 400′ and a forward voltage detector 500′. The forward voltage detector 500′ detects a forward voltage Vf at an anode of the LED 400′ and then supplies the forward voltage Vf to the non-inversion amplification unit 200′. The non-inversion amplification unit 200′ performs a non-inversion amplification to a difference voltage between the reference voltage Vref1 and the forward voltage Vf with a preset gain. The driving unit 300′ adjusts a supply voltage thereof according to the difference voltage from the non-inversion amplification unit 200′ and then supplies the adjusted supply voltage to the LED 400′ so as to regulate the temperature of the LED 400′. However, the foregoing LED control circuit 1′ is so complicated that occupies a relatively larger space and is difficult to meet the demand for miniaturization of electronic products.